CHICO — One person is dead and four are in critical condition following apparent drug overdoses Saturday morning at a house on Santana Court in an incident that Chico police Chief Mike O’Brien described as “horrific.”

“Every indication is that this mass overdose incident was caused from the ingestion of some form of fentanyl in combination with another substance,” O’Brien said at a press conference Saturday afternoon. “That is yet to be confirmed but we do anticipate confirmation in the coming days.”

A Chico Police Department news release listed the address as 1166 Santana Court, just off Ceres Avenue near East Avenue east of Highway 99.

“One male individual was pronounced dead at the scene. We are not releasing any further details on that death,” O’Brien said.

As of Sunday, seven remained in the hospital as police continued their investigation.

“Two were discharged and seven are in good condition,” said Nicole Johansson, marketing and communications manager for Enloe Medical Center.

According to Mike Rodden, Chico police commander, all of the people hospitalized were over 18 and most appeared to be in their 20s. The first reports came in to the police department around 9 a.m., Rodden said.

In addition to those transported to Enloe Medical Center, two police officers were transported as a precaution after they told firefighters on scene they were feeling some effects, O’Brien said.

Chico Fire Department Chief Steve Standridge said CPR was performed on six individuals at the scene, and a total of 12 were transported to Enloe Medical Center.

At the press conference, O’Brien said officers also administered six doses of naloxone when they arrived at the scene.

At the time of the incident, several emergency vehicles were sent to the scene.

“We had four fire engines; all of the Butte EMS were on scene as well. It was a large mass casualty incident for us.,” Standridge said.

In its news release, Enloe Medical Center said 11 people had been taken to their facility. In addition to the four in critical condition, three others were listed as serious, one fair and one undetermined. Two others were treated and released.

O’Brien said though the event is tragic, and there is a possibility for more fatalities, it could have been worse without dispensing the naloxone, a drug which counteracts the effects of opioids.

“These substances are extremely dangerous, and it takes just a very minute amount to cause life-saving conditions,” O’Brien said.

Chico police detectives are now conducting the investigation of the incident, O’Brien said. The residence is being treated as a hazmat site and the Butte Interagency Narcotics Task Force is responsible for the scene.

Currently it is unknown if those who ingested the drug were being targeted and the police are following up on information they received regarding that as part of the investigative process.

Police have Santana Court taped off at Ceres Street. Multiple police vehicles remained at the scene mid-afternoon.

There is no clear time or date when the scene will be cleared, but the neighbors are not at risk.

“It’s not a danger to the public right now,” O’Brien said.

Since the residence is a hazmat scene O’Brien said they are not releasing details regarding the removal of the body from the scene, but they want to handle it respectfully and safely.

“We’ll have additional information as this unfolds and we’ll release that information as soon as we can,” O’Brien said.